Question

Let the magnetic field on earth be modelled by that of a point magnetic dipole at the centre of earth. The angle of dip at a point on the geographical equator ______.

1. is always zero.
2. can be zero at specific points.
3. can be positive or negative.
4. is bounded.

Options

• a, b and c

• a, c and d

• b, c and d

• c and d

Answer 1

b, c and d

Explanation:

Angle of inclination or dip is the angle between the direction of intensity of total magnetic field of the earth and a horizontal line in the magnetic meridian.

If the total magnetic field of the earth is modelled by a point magnetic dipole at the centre, then it is in the same plane of geographical equator, thus the angle of dip at a point on the geographical equator is bounded in a range from positive to negative value.